I decided to install OpenBSD 4.0 which has proven to be an extremely reliable, stable, easy to install and use, secure, Free/Libre Open Source Operating System. What is more, OpenBSD built-in firewall (named PF) is one of the most powerful, comprehensive open source firewalls in the market with support for stateful filtering, traffic normalization, traffic classification (ALTQ), load-balancing and resilience (pfsync) with good logging support (pflog) that, when combined with OpenBGPD and OpenSSH, make it a win-win platform to build network and security-oriented servers and appliances. OpenBSD can be downloaded from http://www.openbsd.org/ftp.html.

My initial expectations were low, to be honest. I have been using older versions of OpenBSD on quite old, low-end systems for a long time. The mini-barebone system has a full array of mostly-new hardware, like the built-in CF/SD/MMC reader, the SATA disk controller, and DDR2 memory. However, it turned out that OpenBSD 4.0 has absolutely no problem at all at dealing with all the integrated hardware. The SATA disk was recognized as such (wd0), the CF/SD/MMC built-in reader is recognized as three different devices (sd0, sd1 and sd2), and the USB 2.0 EHCI and FireWire built-in controllers are properly configured and recognized. Additionally, since the machine sports an Intel Pro 1000/MT Gigabit Ethernet controller, OpenBSD is able to use TCP/UDP checksum offloading (the em driver has been supporting this feature since OpenBSD release 3.8, as far as I know).